Noise-canceling Headphones - How do they work?

What is noise cancelling? How do headphones with this technology work? These are the questions that audiophiles, magazine reviewers, and manufacturers have different answers to. It’s not surprising since there’s a certain speculation on whether it’s a marketing trick or must-have for the headsets that are supposed to provide impeccable listening experience. Moreover, some users doubt this technology is worth the bucks invested into the net price of the headphones. 

In this article, we’ll find out about the technology, the types, and how it works. Additionally, we’ll answer the most frequently asked questions about the subject. Keep on reading and you’ll get to know if a noise cancelling headset is exactly what you should be after. 

What is noise cancelling and how does it work?

How does noise cancelling work? Noise canceling is the technology that is supposed to reduce ambient noise so that a listener could hear only audio and not be disturbed by external sounds. It creates a sort of isolation from the outside world. 

However, not everyone likes it. Some people can’t stand carrying noise-canceling headphones on their heads due to the pressure on the eardrums. Others might feel headaches and even nausea. 

How do noise cancelling headphones work? There are active noise cancellation, passive noise isolation, and adaptive. The first type is a technological name of placing your hands over your ears to seal out incoming noise. With the second one, things are way more interesting. The third technology uses advanced algorithms to process the sound. 

Active noise cancelling technology was invented by Dr. Lawrence Jerome Fogel. He elaborated systems and filed for patents on active noise cancellation in the domain of aviation. The system was supposed to cut down noise for the pilot in the cabin and make the interaction easier. Thus, he was called the inventor of ANC and he worked out one of the first noise cancelling headphones protocols Let’s find out closely how ANC works.

Do noise cancelling earbuds differ from headphones? Not particularly. Since earbuds feature in-ear design, it is thanks to ear-tips and ear-fins that a strong seal should be provided for the passive noise reduction. As for ANC in earbuds, it’s an inbuilt technology working by the same principle in in-ears. 

What is active noise cancelling headphones?

Active noise cancelling headphones mean they build up a buffer that shuts down high-frequency sound waves. They decrease noise by effectively cancelling lower-frequency sound waves. How is that possible? The headset generates its own waves that copy the entering noise.

There are four components that influence the process, such as a microphone, speaker, circuitry, and battery. The microphone usually put inside the ear cups accepts ambient noise that cannot be withdrawn passively. The circuitry means a group of electronics also put into the ear cup that “feels” the input from the mic and produces the “trace” of the sounds from outside, tracking its frequency and amplitude. Afterwards, they construct a new wave which is 180°out of phase with the ones linked with the noise. This is how “anti-noise” is created. 

As for the speaker, it accepts such noise together with an ordinary audio. Thus, the anti-sound eliminates the noise but does not influence the necessary sound waves of the necessary audio.

The battery plays an important role here as well. A headset needs an additional energy to generate the noise-cancelling result. It can get it from a rechargeable battery.

How many decibels do noise cancelling headphones block? With the elements mentioned above, they are capable of reducing the noise of 20 decibels. It signifies that 70% of external noise is actively sealed out. 

ANC headphones: 

• Treblab E3 (Patented Multi-Function Noise Cancelation protects your listening experience)
• Treblab Z2 (Active, T-Quiet™ ANC technology)
• Bose Noise Cancelling Headphones 700
• Sony's WH-1000XM3

What is passive noise cancelling headphones?

Passive noise isolation leans on the capacity of the ear cups of latching securely against the ears and that way blocking out the ambient noise. Passive noise cancelling headsets simply need to have good-fitting ear-cups that embrace the ears and provide a reliable seal around them.

The best passive noise isolation headsets are circum-aural models, which are technically built to enhance noise-filtering features. They are padded with layers of high-density foam or other sound-canceling materia. By the way, it makes them heavier than no noise cancelling headsets. The reduction is noise here is claimed to be 15-20 decibels. 

Passive noise cancellation headphones:

• Beats EP
• Beyerdynamic T51i

What is adaptive noise cancellation?

Adaptive noise cancelling work on headphones manifests in the following way: it suggests using on-board microphones to sense external sound and using forward algorithms to obstruct it respectively. So, how do the headphones perform in this case? The headset listens to the shifts in the environment for a few seconds and then step-by-step it comes into operation. 

In simple words, the technology uses adaptive filters that modify according to a user’s ear size or headphones fit. For each case, adaptive filter can boost the overall energy elimination for a peculiar environment. For example, in an airplane - filters block out more low frequency; in a restaurant - the mid one, etc.

Adaptive noise cancelling headphones:

• Beats Studio 3

Noise cancelling headphones - Who may need them?

Each type of noise cancelling is convenient for some particular activity. Pay attention that noise cancelling headphones used for flights might not be good for commuting. 

For flights or traveling

The most suitable type here is active or adaptive noise cancelling. Jet engines produce up to 80dB of noise inside the airplane, and passive models cannot deal with it. 

For working out

It depends on your wants and needs. Do you want to focus on music and not to hear voices and other noise, then active and adaptive is a perfect fit as well. 

Commuting

Since awareness about the surrounding is important when being outside, then passive models will fit the most in this case. 

Meditation

To focus on music or affirmations, the adaptive type of headphones for meditation will be helpful most of all.

Work in silence

In crowded spaces or in the office when work required concentration, active and adaptive noise cancelling headphones will come in handy.

And who should not use them!

Since passive noise isolation requires a tight seal, a user might feel pressure after a few years of listening. Also, they might feel “stuffed” in temples. Others might complain about dizziness, ear soreness and headache. 

As for active models, they block out ambient noise in a way that you don’t hear what’s going on around. If being outside, near heavy traffic, it might be dangerous. However, they do not override vocals and treble. 

Another disadvantage of ANC is the brain’s perception of a sound shift. When switching to ANC, it may sense it as a decompression, which tells the eardrums they are being “pumped out”. As a result, the pain occurs. Luckily, such reaction is not a common case.

It’s an adaptive model that might be dangerous outdoors since it does block out ambient noise better than other types. Herewith isolating completely a listener. 

Conclusion: should I buy noise cancelling headphones?

What makes headphones noise cancelling? In short, these are the fit or built-in elements that allow processing an ambient noise. Before choosing a headset with a particular type of noise cancelling, take into account your needs, your preferences, and pros and cons of the models. If you’re ok with hearing some noise from the outside for safety measures or you need it for running, then go for passive noise cancellation headphones. If you travel a lot, and airplane engine annoys you, then ANC ones will be ideal. Yet, adaptive models with adaptive filters can customize your listening experience to an environment. This technology can meet personal needs of way more users. However, the headphones with adaptive noise canceling do not work with every budget. 

FAQ

What are the best wireless noise cancelling headphones?

The best wireless noise cancelling headphones are the balance between high-quality sound, noise isolation, and the battery lifespan. Since the technology, except passive one, needs more battery energy and affects audio quality, the best one will be the one that tries to navigate effectively between the three characteristics. Herewith, the headset should provide the best listening experience to a user. 

How effective are noise cancelling headphones?

It depends on the type of noise-cancelling. The passive one isolates from the outside world and yet allows hearing it. Active models deal way better with ambient noise, particularly with bass. But mids and highs - it might let them in into your listening. 

Adaptive type is the best one. It can tailor audio to an environment, which makes it convenient for all activities. 

Does noise cancelling headphones protect hearing / do noise cancelling headphones damage your hearing?

Passive models might cause pressure on eardrums and, that way, after long listening cause the pain. But there’s no direct correlation between technology and hearing deterioration. Active and adaptive types were not noticed as those that might damage the hearing. 

Can noise cancelling headphones be used without music?

The headsets with passive noise isolation cannot work without music since audio is what enables them. The ANC headphones can work without any music since the system features its own power source that simply needs to be charged.

Can you sleep with noise cancelling headphones?

It’s up to every single user. However, the over-ear and on-ear design and a headband, even being flexible, are not comfortable for sleeping.

Do noise cancelling headphones block snoring?

Active or adaptive types can work great to reduce snoring sounds since it’s low-frequency ones. 

Do noise cancelling headphones block voices?

Passive and active noise cancelling do not block voices since it’s mid-frequency sound. The adaptive one can do a great job with it.